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karawin / Ka-Radio32

esp32 version of Ka-Radio (https://github.com/karawin/Ka-Radio) by jp Cocatrix
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amp control #131

Open petanque opened 5 years ago

petanque commented 5 years ago

Im using a PAM8403 as amp and it work great except when there is no audio I can hear a small buzz. I have tried esp-radio and it got a shutdown pin to control it, does Karadio got something like that? a pin that go high/low when there is no audio?

karawin commented 5 years ago

Class D amp are very sensitive to noises. Try to filter or add audio transformers https://othermod.com/raspberry-pi-zero-audio-circuit/ https://fr.grandado.com/products/vodool-ground-loop-noise-isolator-audio-anti-jamming-device-noise-isolator-with-3-5mm-audio-interface-for-home-stereo-l3fe?variant=13650164613235&currency=EUR&gclid=CjwKCAjwnMTqBRAzEiwAEF3ndmhbFacTEIcpFXKXyHRjNpqmc45bbenfLHpBcCJb66e5TqEBMEM-sxoCPhUQAvD_BwE

mfdonmez commented 3 years ago

I hope it helps I searched for 4 months but finally found it. currently no sound problems you search pam8403 vref pin. The secret is in this pin. it should be like this

vs1053 Rpin - 220 ohm R - pam8403 R pin vs1053 Gnd - 47U C. - pam8403 Vref pin ( pma8403 GND pin null ) vs1053 Lpin - 220 ohm R - pam8403 L pin

thnks.